We are presented with 9651 and 4507. Let's work out the sum.

Step 1: We'll start by adding the digits 1 & 7 in column 1 and get 8.

Step 2: We'll start by adding the digits 5 & 0 in column 2 and get 5.

Step 3: We'll start by adding the digits 6 & 5 in column 3 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 4 in column 4 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

So, 9651 + 4507 = 14158.

